Telephone-exchange system



Oct. 9 1923.

F. J. SCUDDER TELEPHONE EXCHANGE SYSTEM Filed March 31. 1921 11 Sheds-Sheet 2 k m Q 7 a s gl FJHHH) /n venfor: Freaenc/aj Scuoden Oct. 9, 1923. 1,470,035 F. J. SCUDDER v TELEPHONE EXCHANGE SYSTEM Filed March 31. 1921 11 Sheets-Sheet 5 o N M W fiw Wm M n 6 I w R FM Mg 4 fi whi l J32;

31 hhh in WT \E m an m 8.. 3% RR at it M win I E m 5 gm Q38 NRQ w$k w D w v RQEMQRQKQRQ mg Q fi N. 33

F. J. SCUDDER TELEPHONE EXCHANGE SYSTEM Filed March -31 1921 ll Sheets-Sheet 5 J wm Oct. 9, 1923 F." J. SCUDDER TELEPHONE EXCHANGE SYSTEM Filed March 31 1921 t e lm/enfor frder/t/c J 5604/06/1 W 61%. M my Oct. 9, 1923.

F. J. SCUDDER TELEPHONE EXCHANGE 'SYSTEM 1 Filed Mach s1 1921- Fob f v R t Md w v H u h u 6 6 s 5 v5 I H w 372w l/ e 9326 1K 9 m m l 2.; cidwmw 1 e f F Rwk .85 k .3 a w: an

Oct. 9., 19 23.

F. J. SCUDDER TELEPHONE EXCHANGE SYSTEM Filed March 31. 1921 1 Sheets-Sheet 9 Oct. 9 1923.

' 1,470,035 F. J. SCUDDER TELEPHONE EXCHANGE SYSTEM Filed March 51 1921 11 Sheets-sheaf, 10

; -W My.

Patented Get. 9, 1923.

rnnnnnrcx J. scnnnnn, or LONG- IsLAnn, new Yon nests-non 'ro wns'rnnn nnn'e- I 1.47am; nriir en sr o tries.

'TRIC COMPANY, rnconronarnn, or rinvfiyonic n. conrona'rion on NEW:

roan.

'. TELEPHGNE-EXQHANGFJSYSTEM.

Application filed irarcii'ai, 192 1., eleria1 11'o. 457,253.

4 TO QZZ 107mmmay concern:

Be it known that I, FREDERICK J. Sor' nniiii, a citizen of the "United States of America, residing at Long Island, in the county oi Queens and State of New York, have in vented certain new and usetnl Improve merits in' Telephone-Exchange Systems, of

which the following is a full, clear; con

cise,' and exact description.

tom and more particularly to a system in which connections are established between.

subscribers lines by 'means of mechanical switching devices.v 1 v a In large telephone exchanges comprising several offices, some of which nayhe closely associated and others of which may hequite widely separated, it is desirable to employ inter-office trunk lines for connecting the diilerent ofiicesof the exchange and tor'extending connections to toll trunks leading to exchanges in distant communities, that are designed to provide the most cflicient talking conditions. This result is attained by providing the trunklines wiiich extend to distant otiices or to distant exchanges with loading coils and h-y omitting such loading coils from inter-ofiice trunks which connect adjacent offices.

Heretotore it has been the practice in large exchanges in which connections are extended by inechanical switchingdevices,v to provide selector switches in the originating offices which are under the control of a coinrnon oilice sending IiifiCllalilSin' fOIQ ex-- tending connections to trunks leauinglto other OillCES, or to other switches local to the These switches are posioriginating office.

tionedin accordance with the office designations of the lines with which the connections are desired. The talking c rcuits extending to the brushes ot the switches are provided with I'QpQfltlllg coils for increasing the efficiency of speech transmission; talking cur-. rent being supplied to the llnQ of the calling subscribers through the primary \Vlli'iihings of these coils.

7 To attain the most cficient transmission of speech through the windiiiqsofithe repeat 7 inc coils and over the different classesjot inter-other: trunks withwhich conn ctions may heestahlishcd, it is desirable to provide for different ratios of transtorination through the windings (if the repeating coils. that is, a greater ratio of transformation it This invention relates to a telephone sys the outgoing oilice trunk is of considerable length and loadedfthan it the trunk is of short length and without loading. lt is also desirable 'tof'coinpletely bypass the repeatof thewindings ot the repeating coil associated with the link circuit in accordancewith the character of the trunk circuit to which a connection is'cxtendedfroin the link circuit. a

New particularly it is an object of thein'lvention to. provide means for altering the nuii'iher or effective turns in the secondary winding of the repeating coil associated with a selector link for producing a desired 'ratio oi turns between the primary and secondary windings of the repeating coil through the sclective positioning of the sequence switch associated with the selector link, i I

In connectionwith this invention the office sender is provided with a'plurality of code registers which are set in accordance with the office designation of a desired line, and with a plurality of locking register relays which are selectively operated in accordance with the setting of the code registers. Certain o'ftheserelays control the circuits of the sender in accordance with the classott the call which is to be established some of the relays through the usual group of counting relays control the setting of the district and ofiice selector switches to extend the call to the oiiice inwhich the desired line terininates, and other of the relays through cooperation of the counting relays control the selective n'ioveinents ot the district sequence switch for the purpose of altering the con-' I cuits and controlling mechanism associated therewith; Fig. 3 shows an office selector switch together with thecircuits and con- Y a portion of the circuitof a'sending me'chanism comprising a stepping relay, a roupfof counting relays, a sequence switch for con trolling the circuits of the sender, and a class sequence switch for altering the, circuits of the sender in accordance with-"the class of th call which is to be extended}v Fig. 8 shows the code registers which are! set in accordance with the first three code; oroliice designation digits dialed by thefca'll ing subscriber, and the steering switch which successively associates the coderegisters and the number registers shown in'Fig. 9 with the impulse'clrcuit extending to the calling subscribers line; Fig. 9 shows number regis- "ters-which are set by the c all ingfsubscriber in accordance with the numerical designation of the desired line Fig. 10 shows groups of translator register relays which are se': lectively operated by the translator switch and pulse machine shown in'Fig. 11 in accordance with the setting of the-code r'egis} ters for determining the setting ofther class} switch shown in Fig. 7, the settingsof' the. district selector shown in Fig.2 and. forset} ting the sequence switch of the district selector to determine the connection of-the'r'e peating coil'into the talking circuit. Fig. 11 shows a translator switch and a development of the pulse'machine drum} for setting the re 'ster relays; and Fig. l2iis' a diagram,

shbwing the manner in whichthe several sheets of the drawing should be arranged" 'toshow as much of a complete organization oi cireuits as1s necessary to illustrate the manner in which the connections may be es tablished between subscribers lines.

The calling subscribers line K" isof the usual type provided with a transmitten're ceiver and. a call bell and since. 1t terminates in a full mechanical exchange is also equipped with an impulse sending dial S of the usual type. V s H The subscribers line terminates in an individual trunk finding switchof'the well known rotary step by step type, which through plurality of wipers,has access to a 7 groupoi trunk lines terminating in district selector switches. The switch is provided with a steppingmagnetfor advancing the'wipers over terminals of the trunk lines in s'earch' of an idle trunk .and for advancing the wipers around to normal position upon the release of the establishedconnections;

. The district scle'otor ,'oliice selector, incoming selector and final-selector diagrammatically disclose d in Figs. 2 to5 inclusive are of the typeshown-and described in the pat eiit to EQB. Craft and J. N. Reynolds No.

1,123,696 issued, J anuary 5, 19151 Each of the, switches has a vertically disposed switch shaft; p rovided withfive sets of 'hrushes, eacl1 brush set having access tea banit of 100 terminal's'. For driving the switch shaft upwardly an tip-drive magnet is provided which when energized presses the switch shaft again t a constantly driven power" drum, and for restoring the switch shaft,

to normalposition a second down-drive mag net: is' provided Whlch when energized presses the switch shaft'against a second con-:

stantly', driven power drum. For determin ing the" particular set of brushes on the switch, shaft to be employed a tripping spindleis provided as described in the patent-hereinbetore referred to. The final sele'c'torswitch difiers from. the other selector switches in being provided with additional means comprising a second up-drive magnet and dri'vmg drum tor driving the switch shaft upwardly at two different speeds, rapldly'during brush selection and group selection, and more slowly duringthe-terminal selection'moveinent of the switch shaft.

The'translator switch TS shown 1n Fig.

1 1 isj of the same type as the switch shown 7 in the aforesaid patent, but is equipped with.

lll'se'ts of b'r ushes arranged in 5 pairs, the

brush sets comprising each pairbeing arranged. to be trip 36d. together. 7

Thefsendef fin erswitch SF shown in Fig.2, the time measure switch TM shown in] Fig-n.6, the'registersteering switch RS shown 'in Fig. 8 and the registers A, B, C,

TH, H,-T; and shown in Figs'S and 9 are of thewell-known step by step type, the wipers of which are advanced by stepping magnets. lVith the exception of sender finder switch SF, the wipers of these registers are restored to normal position by being advanced by their respective stepping magnets around to normal. Finder switch SF has no normalv position, the wipers thereof resting in Contact with the bank terminals last em-- ployed when the switch is, idle.

The pulse machine PM shown in' Fig.. 11 comprises adrum of insulating material in which a plurality of circumferential rows of contact segments are embedded, these segments being connected to a source of current through a clommonslip ring. A plurality or" brushes engage the sewralrows of segments and are arranged to be variously connected 1 to the; contacts. in the 10 banks of translator switch TS through suitable distributing blocks (not shown) for conducting impulses or current from the several segments to the bank terminals of the translator switch.

For controllingthe circuits associated with the several selector switches, and the al No. 1,127,808, issued Februaryi), 1915 and known-in the art as sequence switches. Each sequence switch'comprises a rotatable shat-t driven from a constantly operated source of power through a magnetic clutch memberand carries a plurality of circuit closing cams which at different radial positions of the shaft cause the closure of a plurality of contacts. The cam contacts associated with each sequence switch are closed only in the positions indicated by the numerals associated with each contact with the exception of the master contacts 201, 301, 101, 501, 601, 701 and 751 associated respectively with sequence switches 200, 300, 100, 500, (300, 700- tion of a called subscriber L whose line ter- I inmates in a terminating ofiice Y. The apparatus shown in Figs. 1 and 5 is located in office Y, whereas the remaining apparatus is located in the originating oflice X. It will first be assumed that the Ofiices X and Y are situated adjacent to each other and that therefore the interoflice trunk is short and without loading and that the designation of the desired line is LlSpenard 9,532.

hm'tiaton of full mechanical call.

The calling subscriber upon initiating; a.

call closes a circuit for the line relay 101 of the trunk hunting switch 100, which circuit may be traced from grounded battery through the right hand winding of relay 101, the innermost. lower armature and back con tact of cutoff relay l02 over line conductor- 103, through the substation of subscribers line K, and thence back over line conductor 10 1 to ground at the upper armature and back contact of cutoff relay 102. relay energizes in this circuit and clos'es'a circuit for the stepping magnet 105 of the switch 1.00. which circuit'may' be traced from grounded battery through the winding and armature contacts of magnet 105, conductor 10%, the lowermost armature and back contact of relay 102, the right hand armature and frontvcontact of relay 101, conductor 10? The line and the normal contact; oi the bank to which energizing in this circuit. advances the wipers 108, 109, 110, 111, 112 and 113 of switch circuits of the o'i'iice sender, auxiliary switches are provided. These switches may be of the type described in the patent to Reynolds st 100 to the second contacts of the respective banks towhich they have access. As the second contact which wiper 108 engages-is permanently connected to ground,the mag-- :net 105 continuesto step the wipers to the third set of contacts leading tothe first of the group of trunks to which the switch 100 has'access, p 7

It the firsttrunlr of the group is busy, there will be a ground potential on the test terminal thereof appearing in the lowermost bank of the switch and the switch will therefore continue stepping until an idle trunk is found, upon thetest terminal of which battery potential appears. When this battery potential isencouutered a circuit is closed from battery through the right hand contacts of sequence switch cam 202 of the district selector to which the first idle trunk eXtends,-throu9;h the inner left hand armature and bar-k contact of sleeve relay 226, over test conductor 11a wiper 108, conductor 107. the left hand armature and front contact and left hand winding of relay 1011, conductor 115 and thence to ground through both windin 31s of cutoff relay 102. The energi'zation of the cutoff relay 102 opens the circuit of the stepping magnet 10 5 at its this wiper has access. The magnet 105 upon lowermost armature and back contact and r at its upper armature and back contact, and at its upper armature and frontcontact and uppermost lower armature and front contact. this relay extends the conductors 103 and 10 1 of the subscribers line to the wipers 111 and-113 of the switch and thence to the trunk conductors 116 and 117 leading to theselected district selector. Relay 102 also at itsintermediate lower armature and front contact closes a circuit extending through the right hand winding of sleeve relay 226 of the district selector switch, through the break contacts ot the letthand armature of slow releasing'relay 227, the lower right 7 hand contact of sequence switch cam 203 (1 to sleere conductor 11S, wiper 109, winding of them rgrinal message register magnet 119, conductor 120, the intermediate lower armatureahd' front coi'itact of cutolt relay 102 and thence to ground through the upper winding of the cutofi' relay. The

sleeve relay 226 or the district selector switch energizes in this circuit, but owing to its marginal nature the message register magnet 119 does not energize-at this time.

For making: the calling subscribers .line

H. busy to. all calls incoming theretopbat tery potential. is connected to the multiple. test terminals 121 of-th'e calling-line appear ing iii-the iEEI'lIkS Of all final selectors having access to this ine, over, conductor 122,

grounded battery. lViper' 112 through the i g rounc'led segment 124i prepares acircuit ex- 7 right hand. contactof tending over conductor 12.5 to the hack contact of the right hand armature of line relay "101 preparatory to restoring the finder switch to normal when thecuto'lf relay 102 becomes die-energizedupon the'termination of the connection.

Upon the encrgization of sleeve relay 220 a circuit/is estabhshedfor the line relay 228 I of the district selector switch 250 whi h circuit extends from grounded cattery through the right hand. winding of this relay, the lower 1 H; hand contact of'sequence switch cam 20 1;, conductor 229, the lower contacts of sequence switch cam 205, conductor 230 and thence to ground'throughthe front contact and right hand armature of sleeve relay At its inner left hand armature and front conta t relay 226 connects ground potential to the test conductor 114 of the selcctcd trunk to marl: the trunk busy to other 3 line switches, and at the hack contact of this armature disconnects the source of battery potential which up to the time the. selector switch was seized marked the selector switch as idle, Line relay 101 now deenergizes.

Rela 228, upon'energizing, closes a cir-' uit for driving the sequence switch 200 of the district selector switch out of its normal position 1 and into position 2; this circuit extending from grounded battery through the magnet winding'200, conductor 231, the

upper left hand contact of sequence switch.

ram 200, the inner right hand armature and front contact otrela-y 228 and thence to ground at the lower ri e-ht hand' contact of sequence switch earn 207. The sequence switch magnet energizcsin this circuit and under the control of the master cam 201 drives the sequence switch lnto positlon 2 in which position a circuit is closed'from grounded battery through the winding of relay 227 the upper left hand contact of scqucv switch cam 208 and thence to ground. Relay 227 upon energizing closes holdingcircuit for the sleeve relay 226 extending; through the right hand winding ot relay 220, the make contacts of the left hand armature of relay 227 and thence to the sleeve coifductor 118 over the upper sequence switch cam j-(lito 16) this circuit heing maintained thrcu hposition loot the sequence switch or until relay 227 oec omes decriergized.

;Upon reaching position 2 the sequence switch connects a new holding ground to the test conductor 114i ext-ending over conductor 232 and through the upper right holding ground is maintained nerd-03s ping'magnet 233 of the sender tinder SF extendingfrom grounded battery through the interrupter contacts and winding of mag-1 net 233, the upper left hand contact of sequence switch cam 209 (151' to conductor 23 1 and thence to ground through the inner right liand armature and front contact of relay 22S and the lower right 'hand con. tact of sequence switch earn 207. A circuit is also closed at'th'is time through the winding of stepping magnet 233; the winding of cut in relay 235 and thence to ground at the lower left hand contact of sequence switch cam 208. Relay does not energize at this time, however, since its winding,

is shunted by ground connected to the,

armature of linerelay 228. I

As soon as sequence switch 20 leaves position 1 thejlnitlal GIIGTQIZIDQ circuit ofhne relay 228 is opened at the lower rinht hand' contact of sequence switch cam 20 1, but this relay remains locked over a circuit extendin'gfrom grounded battery through its left hand winding, its left hand arijnature and front contact, the unper lei-3t hand contact of sequence switch cam 210, conductor 236 the lower right hand contact of sequence switch cam 21.1,conductor 237', test wiper 238 of the sender. finder switch SF and to ground at husy contacts of the bank over which this wiper moves. As soon, however, as an idle sender is found. the wiper 238'willfind' no ground on the terminal corresponding to such idle sender and the line relay 228 will thereupon de-cner'gize, opening at its inner ripjl'it hand armature and front contactgthe circuit ex tending through "the stepping magnet and closing at its innerright hand ar1uature and back contact a circuit for driving sequence switch 200 out of position 2 and intoposition 3; This circuit may be traced from grounded battery through the sequence switch magnet 200. conductor 231, the upper right hand contact of sequence switch cam 206 the inner right hand arma ture and back contact of relay 228 and thence to ground at the lower right'hand contact of's'equence switch cam 2 71 i As soon as line relay 228de-encrgizes the shunt around the winding ofyrelay is removed at the inner righthand armature and front contact of relay and relay 235 thereupon energizes in series withstepping magnet 233, the; 7 currentflowing rround'through the inner left-hand arma ture and front contacts of this relay over wiper 238v and the terminal upon which it is resting, conductor 76274. and thence to grounded battery through the left hand through the interrupter 628, the outermost left-hand armature and back contact of relay 629 and thence to groundat-the arma ture and front contact of relay 625. Under the influence of the interrupter 628, the

stepping magnet 626 advances the wipers of the time measure switch TM from their normal resting posltions to the second position contacts in the several banks of connew stepping circuit for advancing the time measure switch from position 2 into position 6, thiscircuit extending from grounded battery through the winding of stepping mag-' not 626. the armature contacts of stepping magnet 626, wiper 633, the Nos. 2 to 5contarts of the bank with which this wiper is associated, which-contacts are tied together, conductor 63 the-outer left hand armature and trout Contact of relay 629 and thence to ground at the armature and front contact of relay 625. This inovcn'icnt of switch TM measures oil a definite time interval before the dial tone is given to the calling subscriber. vRelay 29 also closed a circuit extending iroui grounded battery through the winding of stepping relay 800, conductor 801, the innermost left hand armature and 7 front contact of relay- 629, con ductor 635, wiper 239 of the sender finder SF, conductor 2 10, the; upper left hand contact of sequence switch cam 212 (2 to 103;), trunk conductor 117, wiper 113 of the trunk finding switch 100, upper armature and front contact of relav 102, line conductor 104, through the calling suhscribefs sending dial S, line conductor 103, the innermost lower armature and front contact of relay 102, wiper 111, conduc or 116. the lower left hand contact of sequence switch ram 213 (2 to1O-F conductor 241-1, the outer left hand armature and front contact ofrelay 235, wiper 242 :of" the sender finder SF, conductor 636, the right hand armature and front'contact of rel: 629 and thence to ground through the right hand winding of balancing. resistance coil 6371 The stepping relay 800 energizes in this circuit and at its left hand armature and front contact closes a circuit for the slow releasing relay 802, this circuit eXtending from groundedjbattery through the Winding of'relay 602 and thenc to ground through the left hand armature and front contact of relay 800. A circuit is now closed for sending a dialing tone to the calling subscriber which circuit may be traced from ground through the right hand make contacts of-slow releasing relay 802, conductor 803, wiper SOtof the steering switch RS, the normal contact 805 of the bank with which this wiper .is associated, conductor 806, through the leftha-nd winding of balancing coil 637 and thence to ground through the secondary windin of the tone coil 638. The

tone current flowing in this circuit is inductively transmittedito the substation of the calling subscriber through the right hand winding of balancing coil 637, over the circuit previously traced.

;At the time the sender finder SF seized the idle oflice sender and the @time measure switch TM-advanced outof its normal po sition, a ground potential was connected to test conductor V624: to markthe oilice sender busy to all other sender finders, over a circuit extending from ground through the wiper 630 of the timevmeasnre switch, the contacts of the bank with which this wiper is associated, conductor 640, conductor 6411, the right hand winding of differential relay 625 and thence to the test conductor 624:. The right handwinding of relay 625 being short circuited, this relay is still maintainedflenergized over its left winding. 7

The calling subscriber receiving the dialing tone over the circuit previously traced, proceeds to dial the number of the desired line. Under the assumption that the subscriber desires a connection with a sub scribers line L in an adjacent office, which sul'iscribers line is-lis'ted in the directory'as LlSpenai-d 9532 and that this oilice is reached through a,districtselector; switch 250 and oliice selector switch 350 local to the callingsiubscribefis oflice, and through an incoming selector 4 50 s and a, final selector 550 at the ofiice in which the desired line terminates, the subscriber proceeds to dial three letters corres 'ionding to the office designationiof the oilice. inv which the desired line is located and then dials four digits representing the number of the line in such oflice. In the case assumed, the calling subscriber Will dial the letters L I Sand will then dial the numeralst) 5 8 2. which represent the oflice code, will not only cause the setting of the district selector and oifice selector switchesto choose the desired oflice, but will also cause the selection of a The three letters,

proper talking path for efiicient speech transmission between the otlices, and the set ment therewith; conductor ingrelay 802 and thence to ground throughu. the armature and back contact of stepping" iermining the adjustment of the circuits of the Ollice scnderin accordance with theclass 011: the call which lS being extended.

' Setting the code and nwnc rical registers.

In response to the first impulse dialedby the calling subscriber in accordance with the first letter of the oliice designation the stepping relay 800 dc-energizes and closes a circuit for the stepping magnet 80-7701? the first code'register A, which stepping circuit may be traced from grounded i'iattcry through the left hand armature ,and back contact of preliminary pulse relay 808, conductor 809, the winding of slow release relay 810, conductor 811, the winding of stepping magnet 807, the back contact and outer right hand armature of relay 808 the normal hank contact 812 of the register steering switch RS, Wiper 813 normally in engage- 814- the left hand. armature and front contact of slow releasrelay 800. In response to this impulse the.

stepping magnet 807'advances the wipers of 7' the register one step assoon as the circuit:

. of the stepping magnet'SOY is opened.

Up'o'n'the reenergization of stunning relay SOOfand'in response to success ve impulses of the first code letter L, the register A adyances its wipers n'to contact with the fifth 3t L Y i \J: t 13 l i 2; v1; 4- sc 0; contactsoi 1 s ,anxs. to 11m ns mm the stepping magnet-807 shall remain ener-- gizedflong enough upon each de-energization of stepping relay 80C to cause a complete the armature and hack'contzu step of the register, circuit is closed through relay 841m parallel w th the VJ11'l(l.-

- in" or step )ino' magnet 807 which circuit h a n1 7 may be traced from grounded battery through the inner right hand armature andhack contact of relay 808, inding of relay- 841, Wiper 842, the normal contact 01" the bank with which it associated, the armahire and back contact of stepping magnet 807', and thence to ground at the armature and back contact of relay 800 over the'circuit previously traced. Relay 841 energizes in this circuit'and closes a locking circuit fontseltindependent of the armature con-Q tacts of'relay 800 which locking circuit extends we; the circuit previously traced through the winding of relay 841, through the outer 'it hand arn'iaiurc and hack contact of relay 808, contact'8l2, wiper thence to ground through the'lett hand. ar

to-tl e full extent of its movement, when the i it through relay 841 is opened at the atuie contacts of relay 807. Relay 841 at its right hand armature and front contact closes a holding circuit for slow relay 802 "tact to conductorfiafl. of relay 807, i

nit "0 l the stepp'ing in for holding this relay energized independent oil the energization ol relay 800. V

The slow releasing relay 810 WhlclrWas also energized in the circuit of stepping 'magnet 807 of the register A, maintains its and the winding of slow releasing relay 815,

and this letter relay through its armature "and front contact connects ground potential to the conductor (i lO for insuring that the oilice sender he maintained busy to all sender iindersduring the setting of the regi 'er A. At its right hand armature and out contact, relay 810 also closes a circuit Xtending from grounded batterythroti gh he wind ng of slow releasing relay 816, hrough the Winding of'stepping magnet 817 of the register steerings-Witch RS, over conductor 818 through the right hand armature and front contactof relay 810 and thenoeto round over conduct-or 803 andthe make contacts of the right hand armature of slow releasing relay802; As soon as relay 810 die-energizes, upon the cessation of impulses iloiving-t irough the circuit of stepping mag net 807, the circuit previously traced through relay 816 and stepping magnet 817 is "opened; causing the dee'energization of stomping magnet 81'? which thereupon fadce's the Wipers'of the register steering grinding of stepping magnet 807 0'1" register A, to taewlndmg' of stepping magnet8l9 oi? the register 8 10? releasing relay 816 which was energized in series with the stepping magnet 817 during its energization maintainsa ground potential connected to conductor 64:0 "for holding the sender busy to all sender'finders SF over a circuit erttending'from its armature and front con- With the register-steering switch l'li in position 1 the second series "of impulses chi-res;ionding to the second code litca-oi t'he oflice designation cau es the setting of. B'in. a manner similar to the settin'g ott register'rijthe steppingcin gnetSlf) of registei ll eitendinglroni gi'oun'deail hattei'y through {the left hand armature and back Contact of *relay 8.08, -conductor809, the win'dii lg of slow releasing relay; 810,' conductor 81 the windlng of stepping mangnet 8. e, conduc or A1cl1. RS from engagementwith the nor- 'nia'lf contacts of the respective banks to second t he letter is I, the wipers of the code ii takes a setting on the No. l-couthe banks with which the respecmake contact. Upon the termithe impulses oi the second code letter the slow releasing relay S de-energizes in the manner previously described, causing the increment of the'register steering switch BS from position 1 into position 2, in which position-the control circuit preriously traced through the stepping inagnet 810 ot the code register B is opened-and the control circuit extended through the stepping 'net 822 of the code register C. With the v of the register steering switch RS 1 engagement with the second position contacts of the respective banks with which t y are associated a circuit is established the relay 642 which may be traced 'rcrn grounded orttery through the right hand winding of this relay, conductor 643, contact 823, wiperSO in engagement therewith. conductor S03-and thence to ground the make contacts of the right hand -ature o'f relay 802. -Relay .642 upon aising, closes a locking circuit toritsel't eneing from grounded battery through left hand winding and left hand arrnm ture and Front contact to ground on con ductor 040, and at'its left hand armature and front contact closes a circuit for the control relay 6 1s: of the translator control sequence switch 600-. This circuit extends from. grounded battery through the left ha d winding relay 044, the contact of ure switch cam 002 (1 and 2), the

theme to ground on conductor (340.

Netti 1y, Hie twirneldtor s'w/i/c/L.

liela-y (illencrgg'izes in this circuit and z t its armature and tt'ront contact closes a circuit tordrivingi; the translator control to position 2, this circuit extending; from grounded bat-very through the magnet wind sequence switch 600, the lefthand contact,

1/ queuceswitch cam 603 and thence mind through the oi. relu y (ill. i In its ino'i'cn cnt from 2 1, to position 2 the sequence switch or the control of master contact 601 insures that the sequence switch will mature and front contact or relay G42 and waiueucc switch 000 out of position 1 and in armature aiul lfrout o gizing circuit lay 650 which also energizes. Upon reaching position 2 sequence switch 00( closes a circuit for the up drive magnet1100 ot' the translator switch TS, which circuit extends from grounded battery through the winds ing of n1agnet1100, conductor Zi. 101,ith -2 contact of sequence switch earn (2) ad thence to groundat the armature and trout contact of relay G l i. In response to its onergization magnet 1100 presses the depend.- ing portion of the switch shatt 1-102 of the translator switch TS against the constantly rotating up drive roller 1103 thereby ca us ing the switch shaft 1102 and the hru n sets carried thereby to be moved upwardly. This upward movement continues until the test brush 110% encounters a terminal in the test bank 1105 which has been grounded. through the banlr contacts of code re 'isters A and B. Asso'on as brush 1104 such a terminal a circuit is closed through the right hand winding, of the difi'erent:.ally

wound control relay 64 which may be traced from grounded battery through the right hand windingof this relay, the left hand. contacts of sequenceswitchearn 605,

conductor 1106, testing brush 110 1, t; inal 110?,conductor 1108, contact 82dand wiper 825 of the register A; conductorSQG contact 827 and wiper 828 of the code register B conductor 820' and thence tooroundat the lower left hand contact of: sequence switch cam. 600. (1 to Current flowing through the right hand winding; oi relav 64% differentially balances the relay which thereupon (lo-energizes,opening its armature and front contact "the circuit-previously traced throughihe up drive mas, iet

' 1100 of the translator switch thereby arrest- -windin 600 the u 3 er le ft hand contact oi sequence switch cam 607 (2) and thence to ground at the armature rand'back contact o? relay 611.- V r Upon leaving position 2 the initial en extending through the le 't hand winding;oliure a) 04.4 was opened at the contact oi'r-scq ucnce-switch cam 502. but

this circuitis again established as scenes the sequence switch reaches position 23 and the relay 61 1 therefore again :ene es. Upon reaching position 3 a circuit is tablished for the tripping magnet 1110 otthe translator switch TS, extendiiui; from grounded battery through theiz'inding oft .the'tripping magnet, conductor 1111 and thence to'ground throughthc upper right hand coutact ot sequence switch cam 608' (3 to The trippingniagnet upon ener casing: in this circuit, rotates the tripping-r spindle 1109 to position tripping fingers to i in the pair oi' brush sets of the switch 'lrwhich'have been positioned in operative relation to a pair of tripping fingers on the tripping" spindle upon a subsequent morementot the switch shaft. It willbe assumed that hrush sets 11 12 and1113-shown in Fig. 11 of the drawingare the brush sets which are to be tripped at this time.

W hen sequence switch 600 reaches position 1- a circuit is again closed for the up drive magnet-1100 of the translator switch as previously tracmh through the'armature and front contact of relay 6M1 Whe'n the up drive magnet is thus energizedgthe switch shaft 1102 is driven upwardly and during the firstpartof its movement sinceat this time the tripping spindle 1109 is rotated,

the se ected pair ot' hrushes'1112 and 1113 are tripped Lind during thesulasequent upunril mo ement of the switch shaft the brushes ot these brush sets are caused 'to wipe over the te rrninals of the banks to which they have access until the test brush 'litl icn ages a terminalin the test bank 1105 corresponding to the group setting" oi? the code registers. This terminal has around potential connected thereto, through the wipers ot the code registers. A circuit now established. extending trozn grounded battery through the right hand winding of control relay 6 1 1, the left hand contacts of sequence switch cam G05, conductor 1106, test brush 110 1, jhaulr terminal 111%, conductor 1115, contact 830 and wiper 831 of the code register B, conductor 832, contact and wiper 834 of the code reglster A,

conductor 835 and thence to ground at the "lower left hand contact of sequence switch czun (30R (1 to .5). Upon the closure of this circuit through the right hand ,winding of relay (344-. the relay is ditierentially balanced and le--e'n i.' .eiaces opening at its arniatm'e and trout contact "the ci cuit extending tl'iroug'h up drive magnet .1110 of the switch TS to arrest the upward movement of the switch shaft and to position the selected sets of brushes beneath the groups of hank terminals corresponding to the setting; of the code registers A ant, l3; and closing'at its armature and back contact a circuit extending-- throu'ghthe upper left hand conergization. V opens at 1ts armature and front contact'the ray/0,035

tact of sequence switch cam for drivingsequence switch (300 out oi position and into position 5. llpon leaving position a the initial energizing. circuit extending through the-lett hand winding of relay (Sit is opened at the'contact of sequence switch 02 but is again established as soon the seqiiie'uce switch reaches position 5. Relay 64%, upon re-energizing, closes a circuit for driving sequence switch 000 out o't position 5 and into-position 6wh-ich circuit 1 extemls from battery through the winding of sequence switch magnet 60 the left hand Contact of sequence switch earn 603 and to ground at the armature and front contact of relay 644. a r

in position 6 sequence switch 600 again closes the circuit extending over sequence switch can] 604 and conductor 1101 and through theup driveajnagnet 1100 of trans lator switch TS i The up driveinagnet is thereupon energized causing the movement of the selected sets of brushes ot the translatorswitch over the selected, grou rot ter .minals in the bank to whichthe selected sets of brushes have access and until test brush llOtengages a contact in the bank 1105 upon which ground potential lias heen placed bya circuitextending through the wiper'of the code registerC. "Upon the en "gag'ement of the test brush 1104i with this terminal 1116, a Qircuit" is" established ,through the right hand winding of relay 6441. which may beritraccd from grounded O0 battery through the right hand winding of relay 6 14, the left hand contacts of sequence switch canr 605', conductor. 1106 test brush 110 1, terminal 1116, conductor 1117, contact 836 and wiper 837 ofthe code register (l, which was-set loy the calling subscriber in response to the third code letter S the same manner as registers it and B, thei'ice over conductor 838 and to ground at the lower left hand contact of cam- 60; to 8) oi the translator control sei'iueuce switch (300. The current flowing through the'right hand winding" of relay 6 141 now di'flerea' tiall balances the rela causin its de-en- Belay 6 14; upon tie-energizing,

circuit extending through the up drive magnet 1100 of the translator switch TS; l

and at its armature and back Contact closes a circuit extending through the magnet of sequence switch 600, and through the upper 1 left hai'i'dcontact of sequence switch Cain (307' (6) for driving sequenceswitch 600 out of position 6 and into'position SJ In pass} inc; out of position6-the initialeuergizing circu t of relay 6% 1S opened at the'contact of sequence switch earn 602, and in passing into position a circuit is established for relays 111 8 and 1119, which circuit may be traced from groundedbattery through the Windingsof these relays in parallel, God

ductor 1120, the right hand armature. and back contact of relay 1121, conductor 1122 and thence to ground through th upper right hand contact of sequence switch earn 606 (7 to 14). Relays 1118 and 1119, upon energizing, connect the brushes of the brush sets 1112 and 1115 to the windings of translator register control relays 1000, 1001, 1002, 100e, 1001, and 1005.

During the setting of the translator switch iti and immediately following the setting of Lil-e code registers A, B and C, the calling subscriber has proceeded to dial the tour numerical digits of the nuinber of the desired line causing the setting of the wipers of the thousands register T11 upon the ninth set of contacts in the respective banks to which these wipers have access, the setting of the wipers of the hundreds register H upon the fifth set of contacts in the respective banks to which these wipers have access, the setting of the wipers of the tens register T upon the third set of contacts in the banks to which these wipers have access and the setting of the wipers of the units register U upon the second set of contacts in the banks to which these wipers have access. l ollowing the setting of the units register U, the register steering switch 31:1 moves its wipers to position 7-in which position a circuit is established for advancing the time measure switch TM from position 6 into position 16, this circuit extending from grounded battery through the regis stepping magnet 26 of the time measure switch, wiper 627, the tied contacts of the bank with which this wiper is associated, interrupter 645, conductor 839, No. 7 contact 840 in the bank with which wiper 804 of steering witch BS is associated, wiper 804, conductor 803 and thence to ground throu 'h the make contacts of the right hand 53 j 1 V c, armature of reray 802.

Getting the translator register relays.

Upon the connection of the translator r relays 1000 to 1005 inclusive with the brushes of the brush sets 1112 and 1113 of the translator switch TS, impulses are transmitted thereto from the pulse machine drum 1123. Inthe case assumed, two im- HilSPS are transmitted from grounded batthrough the brush 1124, ring 1125, segrm its 1126, l.)1'usir1127,.ln1nl terminal 1128, r .1120, conductor 1130, inner left hand nature and front contact of relay 1118, conductor 11'L, thence to ground through the winding of class register control relay 1000. Similarly a circuit is established from gr 1' :ie-tl battery through brush 1124, ring 1125. segment 1132, brush 1133, bank terminal 1134., brush'1135, conductor 1136, the inner right hand armature and front contact of relay 1118, conductor 1137 thence to ground through the winding of the district brush register control relay 1001. A circuit i closed for otiice brush register control re lay 1002 which may be traced from'grounded battery through brush 1124, ring 1125, seg me-nt 1132, brush 115 3,'ban1: terminal 1140, crush 11 11, conductor .1142, the outer right hand armature and front contact of relay- 1118, conductor 1143, and thence to ground throughthe windingof relay 1003. 1he circuit, of cities group. register control relay 1004 may be traced from grounded battery through brush 1124, ring 1125, segment 1132, brush 1133, bank terminal 1148, brush 1149, conductor 1150, the inner right hand armature and front contact of relay1119, conduc tor 1151, and thence to ground through the winding of relay 1004. The talking selection registercontrol relay 1005 is energized over a circuit extending from grounded battery through brush 1124, ring 1125, segment 1132, brush 1183, bank terminal 1152, brush 1153, conductor 1154,, the outerrighthand armature and front contact of relay 1119, conductor 1155, and thence to ground through the winding of relay 1005.

Control relay 1000 upon energizing, closes a circuit for energizing relays 1006and 1007 extending from grounded battery through the windings these relays in paralleland thence to ground through the armature and front contact of relay 1000, and the impulses received from the drum of the pulse machine by relay 1000 will thus be transmitted to the windings of relays 1006 and 1007. As soon as the pulse machine has rotatedthe drum to,a point where the brush 1127 engages the first segment 1126 and relays- 1000, 1006 and .1007 are thus energized, a circuit will be closed for the class register relay, 1008 which circuit may be traced from grounded battery, through brush 1124, ring 1125,:'segin'ent 1156. brush 1157, conductor 1158, the inner left hand armature and front contact of relay 1106. conductor 1009 and thence the right hand winding of; class register relay 1008 to ground This relay,

lee

upon energizing, closes a lockingcircuit for itself extending from grounded battery through the upper lefthand contact of sequenceswitch cam 610 (7 to 14%),conductor 646. conductor 1.010 and thence through the left hand, armature and front; contact and t hand winding of relay 1008 to ground. 'hen the pulse machine drum rotates to a position in which the second segment/ 1126 is engaged with brush 1127,.a circuit isestablished for class register relay 1011 which 

